Question

Diana invested $3000 in a savings account for 3 years. She earned $450 in interest over that time period. What interest rate did she earn?

Answer 1

formula I=Prt 450= (3000) r (3) 450=9000r  450/9000=9000r  0.05=r

Answer 2

So she invested $3000. 450 of 3000 would be 0.15 which is 15%. So in one year, interest rate would be 15% divided by 3 years = 5 %
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